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  MG Manual Reference
Ch.10, pp. 14 - 17


Most gardeners use transplants in the garden at some time or another to give long season plants a chance to grow to maturity under their preferred weather conditions, or just to lengthen the harvest season. Tomatoes would certainly have a short harvest period in all but the mid-elevation range of Arizona if started from seed in the ground, and peppers and eggplants might not produce at all if not grown from transplants. Due to the amount of time, attention and need for controlled growing conditions, many gardeners prefer to purchase plants for their gardens. However, for a larger choice in varieties and the control of plant production from seed to harvest, others choose to start their own.
Annual plants
Transplants of annual vegetables and flowers should be stocky, healthy, free from disease, and have good roots. They should not be too small or too mature (tomatoes will transplant all right with fruits already on them, but many other plants will drop flowers or fruit after transplanting). Be sure plants have been hardened-off so that they will easily adapt to environmental change, but they should not be so hardened that they are woody and yellow. Successful transplanting is achieved by interrupting plant growth as little as possible. This is one of the advantages of using peat pots or peat pellets, which do not have to be removed when transplanting.
Have garden soil prepared before transplanting. All additives which require time to break down, such as manures, sulfur, rock fertilizers, and green manures, should be incorporated several weeks before planting. Quick-acting fertilizers and well-decayed compost may be added just before planting
Transplant on a shady day, in late afternoon, or in early evening to prevent wilting. It helps to water the plants several hours before transplanting; when using bare-root plants, such as sweet potato slips or plants from an old-time farm supply store, soak the roots thoroughly an hour or two before setting them out in the garden. They should not be allowed to dry out completely at any time. Handle plants carefully. Avoid disturbing the roots or bruising the stems.
Dig a hole large enough to hold the roots of the plants. Set the plants level with the ground and at recommended intervals. Tomatoes are an exception to the rule of how deep to plant; they will develop roots all along the stems, and you can plant deep enough to leave only two or three sets of leaves exposed. Press soil firmly around the roots of transplants. Pour about a cup of starter solution in the hole around the plant. Use a solution of about half the strength recommended for that type of plant during the normal growing season. Fish emulsion or dilute manure tea may also be used.
For a few days after transplanting, protect plants from wind and sun by placing newspaper or cardboard on their south sides, or by covering with jugs, baskets, or flower pots. Water the plants once a day during the next week if there is insufficient rain. In the following weeks reduce the frequency of water, to every other day the second week and every third day the third week until established. Once established, the type of plant, soil conditions, and weather conditions will dictate how often to water and how much water to apply. Tables 10.6, 10.7 and 10.8 will help in determining irrigation timing.
Perennial plants
When buying small fruit plants and perennial crowns such as asparagus, order early or buy from reliable local outlets. Discount department stores often allow plants to dry up, so watch for this, especially if you are buying sale plants. Select varieties that will do well in your growing conditions. For perennial plants, it will pay to do some research to find out what the major disease and insect pests are and buy resistant varieties. Dormant, bareroot plants and 1 or 2-year-old crowns are preferred. Look for roots that are full, slightly moist, and have color. Roots that are dry brown or soggy black are indicative of poor storage and will probably not give good results. Check crowns for signs of viable buds. Inspect plants for signs of insects or disease. If you receive plants by mail which are not satisfactory, do not hesitate to send them back.
Once you have the plants, keep the roots moist (but not soaking wet) by misting occasionally, and do not allow them to freeze or be exposed to high temperatures. If it is necessary to keep the crowns for more than a few days, place in cold storage (not freezing) or else heel in a trench of moist soil in a shaded location. Pack soil firmly against roots to eliminate any air pockets.
Transplant crowns according to directions, digging holes large enough to give the roots plenty of room to spread. Remove any roots which are discolored or dried out. Perennial plants appreciate a dose of compost mixed into the bottom of the hole. Once transplanted, shade the plants if necessary and water when needed. Extra care at the beginning of their growth will result in productive, healthy plants.
Table 10.5

TRANSPLANT PRODUCTION DATA (Ease of transplanting)Top

Easily Survive
Require Care in
the Operation
Not Successfully Transplanted
by Usual Methods
Broccoli Beets Beans
Cabbage Carrots (young) Corn
Cauliflower Celery Cucumbers
Eggplant Chard Peas
Lettuce Melon (2 true leaves) Okra
Chinese cabbage Squash (2 true leaves)  
Sweet potato slips    
Onion (tends to bolt)    

Adequate soil moisture is essential for good crop growth. A healthy plant is composed of 75% to 90% water, which is used for the plant's vital functions, including photosynthesis, support (rigidity), and transportation of nutrients and sugars to various parts of the plant. During the first 2 weeks of growth, plants are becoming established and must have water to build their root systems.
While growing, vegetable crops need about an inch of water per week in the form of rainwater, irrigation water, or both, from April to September. Keep a rain gauge near the garden or check with the local weather bureau for rainfall amounts, then supplement rainfall with irrigation water if needed. There are ways, however, to reduce the amount of water you have to add.
During dry periods, one thorough watering each week of 1 to 2 inches of moisture (65 to 130 gallons per 100 square feet) is usually enough for most soils. Soil should be wetted to a depth of 12 inches each time you water and not watered again until the top few inches begin to dry out. Average garden soil will store about 2 to 4 inches of water per foot of depth.
Reducing water demands
All of this water, however, may not be available to plants, particularly if the soil is a heavy clay. Clay particles hold soil moisture tightly. If, for example, there are 4 inches of water per foot of this type of soil, there may be as little as 2 inches available for plants. A relatively high level of humus in the soil, brought about by the addition and breakdown of organic matter, can improve this proportion to some extent. By causing clay particles to form aggregates or large clumps of groups of particles, humus also adds air spaces to tight clays, allowing moisture to drain to lower levels as a reserve, instead of puddling and running off the top of the soil.
The moisture-holding capacity of sandy soils is also improved by addition of organic matter. Though most soil water in sandy soil is available, it drains so quickly that plants are unable to reach water after even a few days following a rain. Humus in sandy soil gives the water something to cling to until it is needed by plants. Addition of organic matter is the first step in improving moisture conditions in the garden.
Mulching is a cultural practice which can significantly decrease the amount of water that must be added to the soil. A 4 to 6 inch organic mulch can reduce water needs by as much as 1/2 by smothering weeds (which take up and transpire moisture) and by reducing evaporation of moisture directly from the soil. Organic mulches themselves hold some water and increase the humidity level around the plant. Black or clear plastic mulch also conserves moisture but increases soil temperatures dramatically during the summer (to the detriment of some plants and the benefit of others) if not covered by other mulch materials or foliage.
Shading and the use of windbreaks are other moisture-conserving techniques. Plants that wilt in very sunny areas can benefit from partial shade during the afternoon in summer. Small plants, in particular, should be protected. Air moving across a plant carries away the moisture on the leaf surfaces, causing the plant to need more water. In very windy areas, the roots often cannot keep up with leaf demands, and plants wilt. Temporary or permanent windbreaks can help tremendously.
During those times when cultural practices simply aren't enough, when rainfall is sparse and the sun is hot, watering can benefit the garden with higher yields, or may save the garden altogether in severe drought years.
Irrigation, when properly used, can benefit the garden in many ways:
  • Aids in seed emergence.
  • Reduces soil crusting.
  • Improves germination and plant stand
  • Reduces wilting and checking of growth in transplants.
  • Increases fruit size of tomato, cucumber, and melon.
  • Prevents premature ripening of peas, beans, and sweet corn.
  • Maintains uniform growth.
  • Improves the quality and yields of most crops.

Table 10.6


Intermountain Desert and Western High Plains

  250-300 Days 210-250 Days 180-210 Days 150-180 Days 120-150 Days 90-120 Days
  Season Daily Season Daily Season Daily Season Daily Season Daily Season Daily
Crops Use
Beans 22.0 0.25 17.0 0.20 14.0 0.20 14.0 0.18 14.0 0.17 12.0 0.15
Corn ---- ---- 30.0 0.35 26.0 0.30 24.0 0.28 22.0 0.24 ---- ----
Potatoes ---- ---- 23.0 0.30 21.0 0.28 20.0 0.25 19.0 0.22 17.0 0.20
Peas ---- ---- ---- ---- 10.0 0.19 10.0 0.18 10.0 0.17 9.0 0.15
Tomato ---- ---- 20.0 0.22 18.0 0.20 17.0 0.18 16.0 0.17 ---- ----
Melons 22.0 0.25 20.0 0.22 18.0 0.20 16.0 0.18 ---- ---- ---- ----
Truck Crops 20.0 0.25 18.0 0.22 14.0 0.20 12.0 0.18 12.0 0.16 10.0 0.15
From: Irrigation Principles and Practices. 4th Ed. Vaughn Hansen
Irrigation methods
The home gardener has several options for applying water to plants - a watering sprinkler can, a garden hose with a fan nozzle or spray attachment, portable lawn sprinklers, a perforated plastic soaker hose, drip or trickle irrigation, or a semi-automatic drip system. Quality equipment will last for a number of years when properly cared for. When deciding on which type of watering equipment to use there are a number of things to consider.
Several types of drip or trickle equipment are available. The soaker hose is probably the least expensive and easiest to use. It is a fibrous hose that allows water to seep out all along its length at a slow rate. There are also hoses with holes in them that do basically the same thing; water drips out the holes. With the latter type, a flow regulator usually has to be included with the system so that water can reach the end of the hose, yet not be sprayed out at full force. A special double-wall type of irrigation hose has also been developed which helps to maintain an even flow. Finally, there is the emitter type system, best used for small raised-bed or container gardens, in which short tubes, or emitters, come off a main water supply hose; emitters put water right at the roots of the desired plants. This is generally the most expensive form of irrigation and the most complex to set up, but it has the advantage that the weeds in the area are not watered, and evaporation from the soil is minimized. This type of system is best used in combination with a coarse mulch or black plastic. Drip systems generally have some problems with clogging from soil particles and/or mineral salts from water taken from springs or wells. New designs take into consideration the clogging problem; some include filters and self-flushing emitters. It is wise to make a complete investigation and comparison before purchasing a drip irrigation system.

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